TV in service van?

Status
Not open for further replies.
anthonysolino said:
I had a modifed wave and it TRASHED my dewalt battery cells, I got this one, haven't had any problems, I had an issue with my lap top with my old inverter, this cured it all, its crazy what a pure wave does.
Click to expand...
Any equipment which uses a series capacitance for current limiting from line voltage will behave very badly when exposed to the rapid rise and fall edges of either a full or modified square wave. An a simple diode rectifier to capacitor DC supply will put very high peak currents through the diode(s) with that waveform as an input.
Motors and transformers can be very noisy or worse when that waveform is applied to their windings, even though there may not be excess current.

PS: I agree that "Modified Square Wave" is a far better description than "Modified Sine Wave".
 
ggunn said:
"Modified sine wave" is a misnomer. It's actually a modified square wave.
Click to expand...
I saw a video of a guy putting this one on a O scope and the wave looked pretty pure to me, he zomed in on he scope and see jagged edges on the entire wave length,
* question though its is ONLY possible to obtain pure sinusodal wave form, ie. not square or modified wave from a true AC source? because there is some inverters that are sold like including mine (even ones of course in the 2,000 dollar range) that are sold as pure sine wave out put, or is this still a square wave? I have seen videos of these devices on scopes and they are not square
 
The greater the number of steps, the higher the "resolution" of the synthetic wave, not unlike the sampling rate of digital audio.

I explain it (digital resolution) to people as needing to draw a circle using only straight lines.

I wonder if a 1:1 transformer would filter out the jaggedness.
 
LarryFine said:
The greater the number of steps, the higher the "resolution" of the synthetic wave, not unlike the sampling rate of digital audio.

I explain it (digital resolution) to people as needing to draw a circle using only straight lines.

I wonder if a 1:1 transformer would filter out the jaggedness.
Click to expand...
I would think it would help? the inverter hasn't ruined my batteries at all, and my laptop has been fine, my old one I destroyed it and had to recondition the battery from an AC source, I had to drain it down to zero and recharge it in the house. since then this one has been doing pretty good for 45 bucks I love it, its only 300 watts but heck, I charge a few batteries, a job site radio some times and my computer, its perfect for it!
 
There are two ways to get sinusoid from DC. The first is to use an analog amplifier in linear operating mode to provide the power output.
The second is to use one-off switching elements and pulse width modulation to approximate the desired waveform and add enough filtering that the switching frequency is not seen. This wastes much less energy in dropping the voltage from the DC.
Then there is the third option of only switching the DC, but using periods of +, - and also zero to approximate the sine wave
This is usually refered to as modified sine wave.

Sent from my XT1585 using Tapatalk
 
Last edited:
electrofelon said:
Why would one want tools and wire in there? Sounds like work that would distract from the TV watching experience 😂
Click to expand...
Actually, this was part of a concept vehicle (I think for scuba divers). The guts of the vehicle slide out to make room for TV watching... Lots of room for tools &c...

nv200_02.jpg
 
Status
Not open for further replies.
Top